Exoskeleton continuous-use fit evaluation system and method

ABSTRACT

A method of performing a fit test on an actuator unit coupled to a user. The method includes determining a first configuration of the actuator unit generated in response to actuating the actuator unit while the user is performing one or more movements for the fit test; determining a change from the first configuration of the actuator unit while the user is performing the one or more movements for the fit test; determining that the change from the first configuration corresponds to an improper fit of the actuator unit coupled the user; and generating an improper fit indication that indicates improper fit of at least leg actuator units coupled the user.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/116,298, filed Aug. 29, 2018, which is a non-provisional of andclaims the benefit of U.S. Provisional Application No. 62/551,664, filedAug. 29, 2017, which applications are hereby incorporated herein byreference in their entirety and for all purposes.

This application is also related to U.S. patent application Ser. No.15/953,296, filed Apr. 13, 2018, and is related to U.S. patentapplication Ser. No. 15/823,523, filed Nov. 27, 2017, and is related toU.S. patent application Ser. No. 15/082,824, filed Mar. 28, 2016, whichapplications are also hereby incorporated herein by reference in theirentirety and for all purposes.

BACKGROUND

The performance of a powered exoskeleton device can be directly impactedby how well it is fit to the user. A poorly fit device can significantlyunderperform a properly fit device. Two conventional options foraddressing this issue are professional fitting and extensive trainingmaterial. Professional fitting is impractical for use in more than verycontrolled settings, and even with extensive training, a normal user islikely to encounter difficulty with fit. In view of the foregoing, aneed exists for an improved device to automatically assess the qualityof fit of an exoskeleton device on the user in an effort to maintainhigh levels of performance without requiring professional fitting.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an example illustration of an embodiment of an exoskeletonsystem being worn by a user.

FIG. 2 is an example illustration of another embodiment of anexoskeleton system being worn by a user while skiing.

FIG. 3 is an example illustration of a further embodiment of anexoskeleton system being worn by a user while skiing.

FIGS. 4a and 4b are example illustrations of a still further embodimentof an exoskeleton system being worn on the leg of a user.

FIG. 5 is a block diagram illustrating an embodiment of an exoskeletonsystem.

FIG. 6a illustrates an exoskeleton system worn by a user during a fittest, the exoskeleton system being in an un-actuated state.

FIG. 6b illustrates the exoskeleton system of FIG. 6a in an actuatedstate during the fit test, the actuated state generating a displacementof an upper arm of the exoskeleton system.

FIG. 7a illustrates an exoskeleton system worn by a user during a fittest, the exoskeleton system being in an un-actuated state.

FIG. 7b illustrates the exoskeleton system of FIG. 7a in an actuatedstate during the fit test, the actuated state generating a displacementof an upper and lower arm of the exoskeleton system.

FIG. 8 illustrates a method of performing a static fit test inaccordance with an embodiment.

FIG. 9 illustrates a method of performing a moving fit test inaccordance with an embodiment.

It should be noted that the figures are not drawn to scale and thatelements of similar structures or functions are generally represented bylike reference numerals for illustrative purposes throughout thefigures. It also should be noted that the figures are only intended tofacilitate the description of the preferred embodiments. The figures donot illustrate every aspect of the described embodiments and do notlimit the scope of the present disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In one aspect, this application discloses example embodiments pertainingto the use of worn, powered devices (e.g., exoskeletons) configured toautomatically evaluate the suitability of device fit on a user.Performance of powered devices on their users can depend on how well thedevice fits the user's body. Improper fit can degrade performance, andthere are currently no options beyond better training material andexpert guidance to address this. This disclosure presents a system andmethod for controlling a device to automatically evaluate the quality ofdevice fit and recommending potential issues and solutions to the user.

In one aspect, this disclosure teaches example methods of using apowered exoskeleton device to assess its own fit on a user. For example,this can be done by interpreting sensor response to anappropriately-controlled application of mechanical power to the user.Various embodiments of such methods and systems that implement suchfitting methods are detailed below. For the purposes of this disclosure,some descriptions will consider the scenario of a user who isinteracting with a powered knee exoskeleton. This is done forconvenience and in no way limits the application of this method to otherworn powered devices on other parts of a human or non-human body.

In further aspects, this disclosure relates to systems and methodsdesigned to assess the fit of an exoskeleton on the user. Variousembodiments are configured to evaluate the motion of the exoskeletondevice in response to a system input of mechanical power while theexoskeleton device and user are in a known configuration. In someembodiments, this can involve a deliberate fit test which is run duringdevice start-up or an intentionally triggered test during deviceoperation. However, other embodiments can use design approaches towardsthe timing of the application of this method. Other embodiments caninclude but are not limited to one or more of the following timingapproaches: intermittent comparison of unpowered to powered behaviorduring operation when the device enters one specific state that isoccasionally encountered during operation; repeated comparison ofunpowered to powered behavior within a device configuration that isregularly encountered during operation; continuous comparison ofprevious device operation to current device operation under the samemechanical power input conditions to evaluate deviations over time; andthe like.

One embodiment includes a method to determine if a knee exoskeleton forskiing is appropriately fit to the leg(s) of a user. It should be statedthat the description of this example embodiment is meant for clarity andnot intended to limit the application of further embodiments in any way.In one example embodiment, a powered knee exoskeleton designed to assistthe knee during skiing applications can be worn on both legs of the userwhere respective leg exoskeleton units are mechanically connected to therespective thighs and lower legs of a user. For example, upon startingup, the exoskeleton device can direct the user to get into a seatedposition with knees bent in front of the user with feet firmly fixed tothe ground. The user can be directed to assume this position through avisual cue on a cell phone, or in other suitable ways.

Once in the indicated position, the user can begin the device'sautomated fit evaluation through a button press. At this time, thedevice can record a baseline of sensor signals in this known, unpoweredconfiguration. The exoskeleton device can then begin to introduceassistive knee torque through its knee actuator. In this embodiment, thefit evaluation can be designed such that the exoskeleton device slowlyincreases the torque until a predetermined maximum torque is reached,after which the torque is slowly returned to zero. Throughout thepowered input in this fixed configuration, the device records data fromthe device sensors. The device can then compare the behavior of thedevice under torque to the no torque configuration to determine if thedevice is sufficiently connected to the user. In this embodiment, thedevice can compare the measurement of the knee angle from the unpoweredconfiguration to the knee angle from the powered configuration. If thedevice observes more than a predetermined deviation in knee angle,(e.g., 10 degrees of difference) between the unpowered to poweredconfiguration, then the device can determine that the device isincorrectly fit to the user. This determination can assume that theleg(s) of the user have not deviated significantly from the initialseated position, which, if assumed true, means that any knee angledeviation from the powered input comes from motion of the devicerelative to the leg, indicating incorrect fit.

Another embodiment includes a method to determine if a knee exoskeletonfor medical applications is appropriately fit. In such an embodiment, anexoskeleton device can comprise a single leg, knee exoskeleton designedto provide knee torque assistance during a stationary stance phase of anambulatory gait. In this embodiment, the exoskeleton device can use theconfiguration of the leg in stance phase as a known initial baselineconfiguration. The stance phase can be indicated by a stationarystanding posture of the user. In this embodiment, when the userphysically enters the stance phase, the device identifies that thestance phase configuration has been entered, either through sensor oruser input to the device, and then records a baseline of sensor readingsto measure the current configuration of the device. The device can thenapply a small torque to provide support for the knee during standing. Asthe device begins to add this power, the device can monitor theconfiguration of the device through sensor measurements and can thencompare those powered measurements to the baseline configurationmeasurements.

In this embodiment, the device can use these relative measurements tocomplete two primary fit assessments. First, the device can evaluate thechange in knee angle as a result of introducing power and can determineif the system is poorly fit. Second, the device can identify a specificfit issue that is most indicative of a lower shank or arm of the devicenot being attached appropriately to the user, so the device canspecifically examine the horizontal motion of the lower shank of thedevice during the powered configuration to determine if it has movedmore than is allowable. In various embodiments, the sensors used todetect a knee angle error and the sensors used to detect undesirablelower leg motion can be separate and distinct. After the assessment anddetermination of an issue, the device can provide the user a warning,alert, or the like (e.g., “device strapping should be tightened”, orthat “the lower leg strap should be tightened”) depending on which fitfailure is identified.

Another embodiment includes a method to evaluate the fit of an ankleexoskeleton for walking applications. For example, the device canevaluate the fit of the exoskeleton device on the user in a plurality ofdynamic stance phases throughout the user's walking gait. In oneexample, when the foot contacts the ground, the system can collectinitial measurements regarding the configuration of the device and theinitial unpowered motion of the device. The device can be attached tothe foot and to the lower shank of the user.

In a dynamic stance phase of walking behaviors in various examples, thelower shank mainly rotates around the user's ankle joint. Therefore, thepart of the device connected to the shank should mainly rotate about theankle joint in a similar fashion in such examples. Power can beintroduced to the ankle exoskeleton after ground contact is detected toassist the user's walking behavior. The system can collect measurementsof the motion of the device during this powered configuration. Thesystem can then compare powered and unpowered sensor signals. In such anembodiment, the comparison can be made to evaluate if the device ismoving appropriately with the lower shank in an arc about the anklejoint or if the device is translating up the lower shank of the user. Ifthe device is translating up the leg of the user above a thresholdamount, the exoskeleton system can identify that the poor fit criteriahas been met or a poor fit threshold has been reached and can limit thepower applied by the device while issuing a prompt to the user totighten the lower leg strapping.

Various examples of the present disclosure are presented in the contextof a knee exoskeleton; however, further embodiments relate to other wornpowered devices, which can include but are not limited to: kneeexoskeletons, ankle exoskeletons, hip exoskeletons, elbow exoskeletons,shoulder exoskeletons, wrist exoskeletons, back exoskeletons, neckexoskeletons, exoskeletons with any combination of these joints,wearables, footwear, and more specifically active footwear. In the caseof wearables and footwear, the power addition does not need to be torqueaddition at a joint for this method to be applicable. Devices thatchange stiffness or adjust tightness on a user can also leverage thesame systems and methods in various alternative embodiments.

Turning to FIG. 1, an example of an embodiment of an exoskeleton system100 being worn by a human user 101 is illustrated. As shown in thisexample, the exoskeleton system 100 comprises a left and right legactuator unit 110L, 110R that are respectively coupled to a left andright leg 102L, 102R of the user. In this example illustration, portionsof the right leg actuator unit 110R are obscured by the right leg 102R;however, it should be clear that in various embodiments the left andright leg actuator units 110L, 110R can be substantially mirror imagesof each other.

The leg actuator units 110 can include an upper arm 115 and a lower arm120 that are rotatably coupled via a joint 125. A bellows actuator 130extends between plates 140 that are coupled at respective ends of theupper arm 115 and lower arm 120, with the plates 140 coupled to separaterotatable portions of the joint 125. A plurality of constraint ribs 135extend from the joint 125 and encircle a portion of the bellows actuator130 as described in more detail herein. One or more sets of pneumaticlines 145 can be coupled to the bellows actuator 130 to introduce and/orremove fluid from the bellows actuator 130 to cause the bellows actuator130 to expand and contract as discussed herein.

The leg actuator units 110L, 110R can be respectively coupled about thelegs 102L, 102R of the user 101 with the joints 125 positioned at theknees 103L, 103R of the user 101 with the upper arms 115 of the legactuator units 110L, 110R being coupled about the upper legs portions104L, 104R of the user 101 via one or more couplers 150 (e.g., strapsthat surround the legs 104). The lower arms 120 of the leg actuatorunits 110L, 110R can be coupled about the lower leg portions 105L, 105Rof the user 101 via one or more couplers 150. As shown in the example ofFIG. 1, an upper arm 115 can be coupled to the upper leg portion 104 ofa leg 102 above the knee 103 via two couplers 150 and the lower arm 120can be coupled to the lower leg portion 105 of a leg 102 below the knee103 via two couplers 150. It is important to note that some of thesecomponents can be omitted in certain embodiments, some of which arediscussed within. Additionally, in further embodiments, one or more ofthe components discussed herein can be operably replaced by analternative structure to produce the same functionality.

As discussed herein, an exoskeleton system 100 can be configured forvarious suitable uses. For example, FIGS. 2 and 3 illustrate anexoskeleton system 100 being used by a user during skiing. As shown inFIGS. 2 and 3, the user can wear the exoskeleton system 100 and a skiingassembly 200 that includes a pair of ski boots 210 and pair of skis 220.In various embodiments, the lower arms 120 of the leg actuator units 110can be removably coupled to the ski boots 210 via a coupler 150. Suchembodiments can be desirable for directing force from the leg actuatorunits 110 to the skiing assembly. For example, as shown in FIGS. 2 and3, a coupler 150 at the distal end of the lower arm 120 can couple theleg actuator unit 110 to the ski boot 210, and a coupler 150 at thedistal end of the upper arm 115 can couple the leg actuator unit 110 tothe upper leg 104 of the user 101.

The upper and lower arms 115, 120 of a leg actuator unit 110 can becoupled to the leg 102 of a user 101 in various suitable ways. Forexample, FIG. 1 illustrates an example where the upper and lower arms115, 120 and joint 125 of the leg actuator unit 110 are coupled alonglateral faces of the top and bottom portions 104, 105 of the leg 102.FIGS. 4a and 4b illustrate another example of an exoskeleton system 100where the joint 125 is disposed laterally and adjacent to the knee 103with a rotational axis K of the joint 125 being disposed coincident witha rotational axis of the knee 103. The upper arm 115 can extend from thejoint 125 along a lateral face of the upper leg 104 to an anterior faceof the upper leg 104. The portion of the upper arm 115 on the anteriorface of the upper leg 104 can extend along an axis U. The lower arm 120can extend from the joint 125 along a lateral face of the lower leg 105from a medial location at the joint 125 to a posterior location at abottom end of the lower leg 105 with a portion extending along axis Lthat is perpendicular to axis K.

In various embodiments, the joint structure 125 can constrain thebellows actuator 130 such that force created by actuator fluid pressurewithin the bellows actuator 130 can be directed about an instantaneouscenter (which may or may not be fixed in space). In some cases of arevolute or rotary joint, or a body sliding on a curved surface, thisinstantaneous center can coincide with the instantaneous center ofrotation of the joint 125 or a curved surface. Forces created by a legactuator unit 110 about a rotary joint 125 can be used to apply a momentabout an instantaneous center as well as still be used to apply adirected force. In some cases of a prismatic or linear joint (e.g., aslide on a rail, or the like), the instantaneous center can bekinematically considered to be located at infinity, in which case theforce directed about this infinite instantaneous center can beconsidered as a force directed along the axis of motion of the prismaticjoint. In various embodiments, it can be sufficient for a rotary joint125 to be constructed from a mechanical pivot mechanism. In such anembodiment, the joint 125 can have a fixed center of rotation that canbe easy to define, and the bellows actuator 130 can move relative to thejoint 125. In a further embodiment, it can be beneficial for the joint125 to comprise a complex linkage that does not have a single fixedcenter of rotation. In yet another embodiment, the joint 125 cancomprise a flexure design that does not have a fixed joint pivot. Instill further embodiments, the joint 125 can comprise a structure, suchas a human joint, robotic joint, or the like.

In various embodiments, leg actuator unit 110 (e.g., comprising bellowsactuator 130, joint structure 125, constraint ribs 135 and the like) canbe integrated into a system to use the generated directed force of theleg actuator unit 110 to accomplish various tasks. In some examples, aleg actuator unit 110 can have one or more unique benefits when the legactuator unit 110 is configured to assist the human body or is includedinto a powered exoskeleton system 100. In an example embodiment, the legactuator unit 110 can be configured to assist the motion of a human userabout the user's knee joint 103. To do so, in some examples, theinstantaneous center of the leg actuator unit 110 can be designed tocoincide or nearly coincide with the instantaneous center of rotation ofthe knee (e.g., aligned along common axis K as shown in FIG. 4a ). Inone example configuration, the leg actuator unit 110 can be positionedlateral to the knee joint 103 as shown in FIGS. 1, 2, 3, and 4 a (asopposed to in front or behind). In another example configuration, theleg actuator unit 110 can be positioned behind the knee 103, in front ofthe knee 103, on the inside of the knee 103, or the like. In variousexamples, the human knee joint 103 can function as (e.g., in addition toor in place of) the joint 125 of the leg actuator unit 110.

For clarity, example embodiments discussed herein should not be viewedas a limitation of the potential applications of the leg actuator unit110 described within this disclosure. The leg actuator unit 110 can beused on other joints of the body including but not limited to the elbow,hip, finger, spine, or neck, and in some embodiments, the leg actuatorunit 110 can be used in applications that are not on the human body suchas in robotics, for general purpose actuation, or the like.

Some embodiments can apply a configuration of a leg actuator unit 110 asdescribed herein for linear actuation applications. In an exampleembodiment, the bellows 130 can comprise a two-layerimpermeable/inextensible construction, and one end of the constrainingribs 135 can be fixed to the bellows 130 at predetermined positions. Thejoint structure 125 in various embodiments can be configured as a seriesof slides on a pair of linear guide rails, where the remaining end ofeach constraining rib 135 is connected to a slide. The motion and forceof the fluidic actuator can therefore be constrained and directed alongthe linear rail.

FIG. 5 is a block diagram of an example embodiment of an exoskeletonsystem 100 that includes an exoskeleton device 510 that is operablyconnected to a pneumatic system 520. The exoskeleton device 510comprises a processor 511, a memory 512, one or more sensors 513 and acommunication unit 514. A plurality of actuators 130 are operablycoupled to the pneumatic system 520 via respective pneumatic lines 145.The plurality of actuators 130 include a pair of knee-actuators 130L,130R that are positioned on the right and left side of a body 100. Forexample, as discussed above, the example exoskeleton system 100 shown inFIG. 5 can comprise a left and right leg actuator unit 110L, 110R onrespective sides of the body 101 as shown in FIGS. 1-3.

In various embodiments, the example system 100 can be configured to moveand/or enhance movement of the user wearing the exoskeleton system 110.For example, the exoskeleton device 510 can provide instructions to thepneumatic system 520, which can selectively inflate and/or deflate thebellows actuators 130 via pneumatic lines 145. Such selective inflationand/or deflation of the bellows actuators 130 can move one or both legs102 to generate and/or augment body motions such as walking, running,jumping, climbing, lifting, throwing, squatting, skiing or the like. Infurther embodiments, the pneumatic system 520 can be manuallycontrolled, configured to apply a constant pressure, or operated in anyother suitable manner.

In some embodiments, such movements can be controlled and/or programmedby the user 101 that is wearing the exoskeleton system 100 or by anotherperson. In some embodiments, the exoskeleton system 100 can becontrolled by movement of the user. For example, the exoskeleton device510 can sense that the user is walking and carrying a load and canprovide a powered assist to the user via the actuators 130 to reduce theexertion associated with the load and walking. Similarly, where a user101 wears the exoskeleton system 100 while skiing, the exoskeletonsystem 100 can sense movements of the user 101 (e.g., made by the user101, in response to terrain, or the like) and can provide a poweredassist to the user via the actuators 130 to enhance or provide an assistto the user while skiing.

Accordingly, in various embodiments, the exoskeleton system 130 canreact automatically without direct user interaction. In furtherembodiments, movements can be controlled in real-time by a controller,joystick or thought control. Additionally, some movements can bepre-preprogrammed and selectively triggered (e.g., walk forward, sit,crouch) instead of being completely controlled. In some embodiments,movements can be controlled by generalized instructions (e.g. walk frompoint A to point B, pick up box from shelf A and move to shelf B).

In various embodiments, the exoskeleton device 100 can be operable toperform methods or portions of methods described in more detail below orin related applications incorporated herein by reference. For example,the memory 512 can include non-transient computer readable instructions,which if executed by the processor 511, can cause the exoskeleton system100 to perform methods or portions of methods described herein or inrelated applications incorporated herein by reference. The communicationunit 514 can include hardware and/or software that allow the exoskeletonsystem 100 to communicate with other devices, including a user device, aclassification server, other exoskeleton systems, or the like, directlyor via a network.

In some embodiments, the sensors 513 can include any suitable type ofsensor, and the sensors 513 can be located at a central location or canbe distributed about the exoskeleton system 100. For example, in someembodiments, the exoskeleton system 100 can comprise a plurality ofaccelerometers, force sensors, position sensors, pressure sensors, andthe like, at various suitable positions, including at the arms 115, 120,joint 125, actuators 130 or any other location. Accordingly, in someexamples, sensor data can correspond to a physical state of one or moreactuators 130, a physical state of a portion of the exoskeleton system100, a physical state of the exoskeleton system 100 generally, and thelike. In some embodiments, the exoskeleton system 100 can include aglobal positioning system (GPS), camera, range sensing system,environmental sensors, or the like.

The pneumatic system 520 can comprise any suitable device or system thatis operable to inflate and/or deflate the actuators 130 individually oras a group. For example, in one embodiment, the pneumatic system cancomprise a diaphragm compressor as disclosed in related patentapplication Ser. No. 14/577,817 filed Dec. 19, 2014 and/or a poppetvalve system as described in U.S. patent application Ser. No.15/083,015, filed Mar. 28, 2016, which issued as U.S. Pat. No.9,995,321.

As discussed herein, various suitable exoskeleton systems 100 can beused in various suitable ways and for various suitable applications.However, such examples should not be construed to be limiting on thewide variety of exoskeleton systems 100 or portions thereof that arewithin the scope and spirit of the present disclosure. Accordingly,exoskeleton systems 100 that are more or less complex than the examplesof FIGS. 1, 2, 3, 4 a, 4 b and 5 are within the scope of the presentdisclosure.

Additionally, while various examples relate to an exoskeleton system 100associated with the legs or lower body of a user, further examples canbe related to any suitable portion of a user body including the torso,arms, head, legs, or the like. Also, while various examples relate toexoskeletons, it should be clear that the present disclosure can beapplied to other similar types of technology, including prosthetics,body implants, robots, or the like. Further, while some examples canrelate to human users, other examples can relate to animal users, robotusers, various forms of machinery, or the like.

FIG. 6a illustrates an exoskeleton system 100 being worn by a user 101during a fit test. The user 101 is shown sitting in a chair 600 with theleg 102 having the exoskeleton system 100 in a bent configuration suchthat the lower arm 120 is disposed along axis L_(I1) and the upper arm115 is disposed along axis U_(I1).

The exoskeleton system 100 in FIG. 6a is shown in a non-actuated state.For example, the actuator 130 can be in an unpowered or neutral statewhere the actuator 130 does not apply force to the upper and lower arms115, 120 toward a linear configuration or away from a linearconfiguration. However, in various embodiments, such an unpowered orneutral state of the actuator 130 can include a nominal force beingapplied to the upper and lower arms 115, 120, with such a nominal forceproviding rigidity to the exoskeleton system 100 without pushing orpulling the upper and lower arms 115, 120.

In contrast, FIG. 6b illustrates the exoskeleton system of FIG. 6a in anactuated state during the fit test, the actuated state applying force tothe upper and lower arms 115, 120 toward a linear configuration andgenerating a displacement of an upper arm 115 of the exoskeleton system100. As discussed herein, a leg actuator unit 110 of an exoskeletonsystem 100 can be secured to a leg 102 of a user 101 via a plurality ofcouplers 150. In the example of FIGS. 6a and 6b , the upper arm 115 issecured to the upper leg portion 104 via a first and second coupler150A, 150B and the lower arm 120 is secured to the lower leg portion 105via a third and fourth coupler 150C, 150D.

In various embodiments, the couplers 150 can comprise straps thatsurround portions of the leg 102 of the user 101 such that the upper andlower arms 115, 120 are securely coupled to the upper and lower portions104, 105 of the leg 102 so that movement of the upper and lower arms115, 120 generates movement of the leg 102 about the knee 103 withoutsubstantial movement of the upper and lower arms 115, 120 relative tothe upper and lower portions 104, 105 of the leg 102. However, where oneor more of the couplers 150 are not securely fastened about the leg 102,actuation of the upper and lower arms 115, 120 can result indisplacement of one or both upper and lower arms 115, 120 about theupper and/or lower portions 104, 105 of the leg 102.

For example, as shown in FIG. 6b compared to FIG. 6a , actuation of theexoskeleton system 100 has resulted in displacement of the upper arm 115relative to the upper portion 104 of the leg 102 by an angle θ_(D1)defined by difference between the upper arm initial axis U_(I1) and theresulting upper arm displacement axis U_(D1). In various examples, sucha displacement of the upper arm 115 can be caused by at least the firstcoupler 150A being inadequately secured to the upper portion 104 of theleg 102 or caused by both the first and second couplers 150A, 150B beinginadequately secured to the upper portion 104 of the leg 102.

However, it should be noted that in the example of FIGS. 6a and 6b , thelower arm 120 does not experience displacement about the lower portion105 of the leg 102. In other words, the lower arm 120 substantiallymaintains alignment along axis L_(I1) while the exoskeleton system 100is in both the un-actuated and actuated states of FIGS. 6a and 6brespectively. In various examples, such maintaining alignment along axisL_(I1) while the exoskeleton system 100 is in both the un-actuated andactuated states can be due to one or both of the third and fourthcouplers 150C, 150D being suitably securely coupled to the lower portion105 of the leg 102.

In further examples, both the upper and lower arms 115, 120 canexperience displacement about the leg 102 from an un-actuated state toan actuated state. FIGS. 7a and 7b illustrate such an example.Specifically, FIG. 7a illustrates the exoskeleton system 100 in anun-actuated configuration (e.g., as in FIG. 6a ), with FIG. 7billustrating exoskeleton system 100 in an actuated configuration (e.g.,as in FIG. 6b ). However, in contrast to FIG. 6b , both the upper andlower arms 115, 120 can experience displacement about the leg 120 withthe upper and lower arms 115, 120 initially being disposed along axesU_(I2), L_(I2) in the unactuated state shown in FIG. 7a and beingrespectively displaced to axes U_(D2), L_(D2) in the actuated stateshown in FIG. 7 b.

Such displacement can be caused by one or more of the first, second,third and fourth couplers 150A, 150B, 150C, 150D being inadequatelysecured to the leg 102. For example, one or both of the first and secondcouplers 150A, 150B can be inadequately secured to the upper portion 104of the leg 102, and one or both of the third and fourth couplers 150C,150D can be inadequately secured to the lower portion 105 of the leg102. Additionally, in this example, the joint 125 is also shown beingdisplaced between FIGS. 7a and 7 b.

While the examples of FIGS. 6a, 6b, 7a and 7b illustrate an exoskeletonsystem 100 having at least one leg actuator unit 110 with the upper arm115 secured to the upper leg portion 104 via a first and second coupler150A, 150B and the lower arm 120 secured to the lower leg portion 105via a third and fourth coupler 150C, 150D, further configurations ofcouplers 150 and/or exoskeleton systems 100 are also within the scope ofthe present disclosure and the examples of FIGS. 6a, 6b, 7a and 7bshould not be construed to be limiting on the wide variety ofalternative embodiments. For example, in some embodiments, an upper arm115 and lower arm 120 of a leg actuator unit 110 can respectivelycomprise one or more couplers 150, including one, two, three, four,five, ten, fifteen, twenty, or the like.

As discussed herein, in various embodiments a fit test can be performedto identify issues with the fit of an exoskeleton system 100 to a user101. For example, a fit test can determine whether one or more couplers150 of an exoskeleton system 100 are improperly fit or secured to theuser 101. Such fit tests can be conducted while the user 101 is staticor moving.

Turning to FIG. 8, a method 800 of performing a static fit test isillustrated, which in some examples can be performed by an exoskeletondevice 510 of an exoskeleton system 100 (see e.g., FIG. 5). The methodbegins at 810 where a static fit test is initiated. For example, in someembodiments, a static fit test can be part of an exoskeleton systemstartup or power-on routine once the exoskeleton system 100 has beencoupled to a user 101 or can be performed at any desirable time (e.g.,when initiated by the user 101, a technician, or automatically based ona determination of exoskeleton performance issues).

At 820, a fit testing position indication is generated, and at 830 adetermination is made that the user has assumed the fit testingposition. For example, a fit test can be designed to be performed withthe user 101 and exoskeleton system 100 in a specific configuration, andthe fit testing position indication can include an instruction for theuser 101 to assume the specific configuration that the test should beperformed in. Such an instruction can include an audio, visual and/orhaptic indication (e.g., via an exoskeleton device 510, a smartphoneassociated with the exoskeleton system 100, or the like). Determiningthat the user 101 has assumed the fit testing position can be based onsensor data from the exoskeleton device 100, based on an indication froma user 101 (e.g., a button press), and the like.

The static position that the test is to be performed in can be varioussuitable positions, which may or may not be selectable (e.g., by a user101, technician, or automatically). For example, the test position caninclude a sitting position with at least one leg 102 of the user 101 ina bent configuration as shown in FIGS. 6a, 6b, 7a and 7b or a standingposition with the exoskeleton system 100 in a generally linear andextended configuration.

At 840, the configuration of an actuator unit 110 of the exoskeletondevice 100 can be determined. For example, the configuration of theactuator unit 110 can be determined based on sensor data from one ormore sensors 513 of the actuator unit 110, such as one or more rotaryencoder, torque sensor, gyroscope, force sensor, accelerometer, positionsensor, and the like, associated with various suitable portions of theactuator unit 110 including the upper arm 115, lower arm 120, joint 125,and the like. While some embodiments can use data from a large pluralityof sensors 115 disposed in separate locations of an actuator unit 110,further examples can use data from a limited number of sensors 115 in alimited number of locations of the actuator unit 110. For example, oneembodiment can rely only on data from a single encoder. Anotherembodiment can rely only on data from a single encoder and a singletorque sensor.

Returning to the method 800, at 850, the actuator unit 110 is actuatedwith the user remaining in the fit testing position, and at 860 a changein actuator unit configuration during actuation of the actuator unit 110is determined. For example, actuation of the actuator unit 110 cancomprise inflation and/or deflation of a bellows actuator 130 or othersuitable type of actuator (e.g., electric actuator, pneumatic actuator,or the like). In some embodiments, actuation can be in a singledirection compared to the starting configuration. For example, usingFIGS. 6a , and 6 b as an illustration, the bellows actuator 130 can beinflated to apply force to increase the angle between the upper andlower arms 115, 120, which in this example generates a determineddisplacement change of the upper arm 115 of θ_(D1).

However, in further embodiments, actuation during a fit test can includeactuation in two directions from a starting point. For example, inaddition to actuating the actuator unit 110 to apply force to increasethe angle between the upper and lower arms 115, 120, force can also beapplied to decrease the angle between the upper and lower arms 115, 120.Where both a positive and negative displacement is generated from such apositive and negative actuation during a fit test, such determinedpositive and negative displacements can be considered separately and/ortogether. Similarly, displacements as shown in FIGS. 7a and 7b can begenerated and identified.

Actuation of the actuation unit can be done in various suitable ways.Using FIGS. 6a and 6b as an example, in one embodiment, starting at theinitial configuration of FIG. 6a , increasing force can be applied bythe actuator 130 until a maximum torque threshold is reached and adetermined displacement can be calculated based on the change inconfiguration from the starting point to the configuration at themaximum torque threshold. In another example, increasingly pulsing forcecan be applied by the actuator 130 until a maximum torque threshold isreached. In a further embodiment, increasing force in a first directioncan be applied by the actuator 130 until a maximum torque threshold isreached; and then increasing force in a second direction can be appliedby the actuator 130 until a maximum torque threshold is reached. Cyclingbetween the first and second direction (e.g., positive and negativedirection) can occur any suitable plurality of times in someembodiments.

A power profile applied during a fit test can be different in someembodiments. In one embodiment, the exoskeleton system 100 can provide aconstant application at a comfortably low torque. The exoskeleton system100 can then use onboard sensors to assess the appropriateness of thefit. In another embodiment, the exoskeleton will apply torque in anon-constant state. A specific embodiment of this method applies torqueto the operator at a set frequency, 1 Hz for example. By applying thetorque at a set frequency, the onboard sensors will be able to assessdifferent aspects of the device fit on the operator. The aboveembodiments are provided as description and are not meant in any way tolimit the possible methods for applying torque which, for clarity, caninclude but are not limited to the following: constant, fixed frequency,variable frequency, various constant forces, random pulses, and thelike.

Returning to the method 800, at 870 a determination is made whether thechange in the configuration of the actuator unit 110 during actuationcorresponds to an improper fit of the actuator unit 110 to the user 101.If the determined configuration change is determined to not correspondto an improper fit, then at 880, a proper fit indication is generated.However, if the determined configuration change is determined tocorrespond to an improper fit, then at 890, an improper fit indicationis generated. Additionally, in some embodiments, where a determinationof improper fit is made, power, actuation capacity, range of motion, orother capability of the exoskeleton system 100 can be limited for thesafety of the user 101 until a subsequent fit test determines proper fitto a user 101.

Determining whether a change in the configuration of the actuator unit110 during actuation corresponds to an improper fit of the actuator unit110 to the user 101 can be done in various suitable ways. For example,where a displacement of one or both of the upper and lower arm 115, 120(e.g., displacement angle θ_(D1) of FIG. 6b or displacement shown inFIG. 7b ) is determined to be at or above a defined threshold, then adetermination can be made that such a displacement or change in theconfiguration of the actuator unit 110 during actuation corresponds toan improper fit of the actuator unit 110 to the user 101. In exampleswhere test actuation occurs in more than one direction from an initialconfiguration, a determination can be made whether displacement orchange in either direction exceeds a threshold or a determination can bemade whether combined displacement or change in both directions exceedsa threshold.

In another embodiment, the actuation unit 110 provides a time-varyingtorque while the user 101 maintains a fixed position as discussedherein. In this case, the exoskeleton system 100 can use sensors (e.g.,sensors 513) to determine an angle between the upper and lower arms 115,120 as well as the relative motion of the various portions of theexoskeleton system 100 such as the upper and lower arms 115, 120. In oneexample, a determination can be made that, while the angle deviation ofthe joint 125 is at an acceptable level and the upper arm 115 of theactuation unit 110 does not move significantly under power, the lowerarm 120 is experiencing significant motion caused by improper fit oflower leg straps 150C, 150D.

In yet another embodiment, the exoskeleton system 100 can apply a slowlyincreasing torque to a joint 125 of an actuation unit 110. In oneexample, sensor data can indicate a moderate amount of motion near thebeginning of force application but that the deviation of lower legorientation remains constant at higher torque. The exoskeleton system100 may then interpret its motion relative to the user insufficient totrigger the safety threshold, and as a result, not stop operation of thedevice. However, the exoskeleton system 100 can infer sub-optimalcoupling between the exoskeleton system 100 and the user 101 (e.g.,inadequate tightness of one or more couplers 150) and intelligentlyaccount for “slop” or displacement between the exoskeleton system 100and the user 101. As discussed herein, the exoskeleton system 100 canindicate to the user 101 to tighten straps of couplers 150 on a specificportion of concern.

Further embodiments can assess and provide an indication associated withvarious other suitable aspects of fit between an exoskeleton system 100and user 101, which include but are not limited to: specific joint angledeviations; device segment angle deviations; angle deviations that arefunctions of variable forces applied; angle deviations that arefunctions of variable frequencies applied; specific straps are notconnected; specific straps require tightening; or the device requires ahardware service to fit properly.

Further embodiments can use other suitable sensor data or calculatedinformation to determine an improper fit of the actuator unit 110 to theuser 101. For example, in one embodiment, sensors can be used todetermine contact or lack of contact between the user 101 and one ormore portions of the actuator unit 110. In another embodiment, sensorscan be used to determine tension of straps of couplers 150. In a furtherembodiment, sensors can identify lateral displacement of portions of anactuator unit 110 (e.g., upper arm 115, lower arm 120, joint 125, andthe like).

Determining improper fit of the actuator unit 110 to the user 101 canhave various suitable levels of specificity. For example, in someembodiments, such a determination can be at the actuator unit 110 level.In other words, a determination can be made of improper fit of theactuator unit 110 to the user 101 without further specificity. Inanother embodiment, an improper fit determination can be at acomponent-level. For example, a determination can be made that the upperarm 115 and/or lower arm 120 of an actuator unit 110 are improperly fitwithout further specificity. In a further embodiment, an improper fitdetermination can be at a coupler-level. For example, a determinationcan be made that one or more couplers (e.g., a first, second, third orfourth coupler 150A, 150B, 150C, 150D).

Such levels of determination can be used to provide instructions to auser 101 or technician for correcting the fit issue. For example, wherean improper fit indication is at the actuator unit level, an improperfit indication can include an instruction to tighten loose couplerstraps on a right and/or left actuator unit 110R, 110L of an exoskeletonsystem 100. Where an improper fit indication is at the coupler-level, animproper fit indication can include an instruction to tighten a firstloose coupler strap 150A on the upper arm 115 of a first actuator unit110 of an exoskeleton system 100.

In further embodiments, any other suitable adjustments or remedies canbe recommended based on determined improper fit. For example, a user canbe instructed to shorten or lengthen a portion of an upper and/or lowerarm 115, 120; to increase or decrease a friction or bias associated witha joint; to replace or service a portion of an exoskeleton system 100;to switch out a modular component for a different modular component, andthe like.

In various embodiments a fit test can be performed by actuating a singleactuator during a given fit test session. For example, where anexoskeleton system comprises a first and second actuator unit 110R,110L, with each actuator unit comprising a single respective bellowsactuator 130 (e.g., as shown in FIG. 1) a separate fit test can besequentially performed on each actuator unit or can be performedsimultaneously on both the actuator units. Additionally, in someembodiments a given actuator unit 110 can comprise a plurality ofactuators 130. In such embodiments a given fit test can be performed onthe actuator unit by actuating the plurality of actuators separately andsuccessively; by actuating the plurality of actuators simultaneously; byactuating a subset of the actuators successively; and the like.

While some embodiments include a static fit test method (e.g., as inFIG. 8) where a user 101 substantially maintains the same positionduring the fit test, further embodiments can include a fit testperformed while a user 101 is moving. For example, FIG. 9 illustrates anexample method 900 of performing a moving fit test, which in someexamples can be performed by an exoskeleton device 510 of an exoskeletonsystem 100 (see e.g., FIG. 5).

The method 900 begins at 910 where a moving fit test is initiated, andat 920 a moving fit test movement indication is generated. For example,a moving fit test can be initiated similar to how a static fit test isinitiated as discussed herein, and a fit test movement indication can begenerated in a similar way as in a static fit test. However, for amoving fit test, a user 101 can be instructed to perform or prepare toperform one or more movements for the moving fit test instead ofassuming a static position. Such one or more movements can includewalking, running, standing from a sitting position, sitting from astanding position, squatting, bending and/or extending a single leg, andthe like.

At 930, a determination can be made that the user 101 has assumed aninitial fit testing dynamic stance phase, and at 940 an actuator unitconfiguration in the initial dynamic stance phase is determined. At 950,one or more actuator units 110 of an exoskeleton system is actuatedduring user movement, and at 960 a change in actuator unit configurationis determined during user movement. At 970 a determination is madewhether the change in the configuration of the actuator unit 110 duringactuation corresponds to an improper fit of the actuator unit 110 to theuser 101. If the determined configuration change is determined to notcorrespond to an improper fit, then at 980 a proper fit indication isgenerated. However, if the determined configuration change is determinedto correspond to an improper fit, then at 990 an improper fit indicationis generated.

For example, while the user 101 is performing one or more movements,data from sensors (e.g., sensors 513 of an exoskeleton device 510 of anexoskeleton system 100 as shown in FIG. 5) can be used to determinewhether improper fit of the exoskeleton system 100 to the user 101 ispresent. In some examples, data obtained during the moving fit test canbe compared to data sampled during user movement with ideal fitconditions and/or incorrect fit conditions. For example, one or moresets of comparison data can be generated by having one or more testusers move in an exoskeleton system 100 while the exoskeleton system 100is coupled to the test user with proper fitting and/or improper fittingof various specificities.

In various embodiments, data from test movement of test users can beused to generate a data profile for movement with proper fit of theexoskeleton system 100 of a user and/or improper fit of the exoskeletonsystem 100 to the user. Improper fit profiles can be generated forvarious improper fit conditions. One example can include a profile forimproper fit of an upper arm 115 of an actuation unit 110, improper fitof a lower arm 120 of an actuation unit 110, and improper fit of boththe upper and lower arms 115, 120 of an actuation unit 110. Anotherexample can include a profile for improper fit of a first coupler 150A;improper fit of a second coupler 150B; improper fit of a third coupler150C; improper fit of a fourth coupler 150D; improper fit of a first andfourth coupler 150A, 150D; improper fit of a second and third coupler150B, 150C; improper fit of a first, second and fourth coupler 150A,150B, 150D; improper fit of a first, second, third and fourth coupler150A, 150B, 150C, 150D; and the like.

Accordingly, by comparing data from movement during a fit test to one ormore data profiles for proper and/or improper fit, a determination ofproper and improper fit can be made and/or a determination of specificfit issue at various levels of specificity can be identified based onmatching of the moving fit test data with a given data profile forimproper fit. Also, while the present example is discussed relative to amoving fit test, use of data profiles can be applied to static fittesting as discussed herein.

In further embodiments, determining proper fit or improper fit of anexoskeleton system 100 to a user 101 during a moving fit test can bedone in various suitable ways. For example, the method 900 can includeevaluating the fit of the exoskeleton system 100 on the user 101 in aplurality of dynamic stance phases throughout a movement of a user(e.g., a walking gait).

In one example, when the foot of the user contacts the ground, theexoskeleton system 100 can collect initial data regarding theconfiguration of the exoskeleton device 100 and the initial un-actuated(e.g., unpowered or un-power-assisted) motion of the exoskeleton device100. The exoskeleton device 100 can be attached to the foot and to thelower leg 105 of the user 101 (e.g., via third and/or fourth couplers150C, 150D, or the like). In a dynamic stance phase of walkingbehaviors, in various examples, the lower portion of the lower leg 105substantially rotates around the ankle joint of the leg 102 of the user101. Therefore, the part of the exoskeleton device 100 connected to thelower leg portion 105 should ideally rotate about the ankle joint in asimilar fashion in such examples.

As part of a moving fit test, actuation can be introduced to an ankleportion of the exoskeleton system 100 after ground contact is detectedto assist the walking behavior of the user 101. The exoskeleton system100 can collect sensor data to measure the motion of the exoskeletondevice 100 during this actuated configuration. A comparison can be madebetween the un-actuated and actuated states (e.g., between powered andunpowered states) to determine whether the exoskeleton system 100 orportions thereof are properly fit to the user 101.

In an embodiment, such a comparison can be made to evaluate if theactuation unit 110 is moving appropriately with the lower leg portion105 in an arc about the ankle joint or if the actuation unit 110 istranslating up the lower leg portion 105 of the user 101. If the deviceis translating up the leg 102 of the user 101 above a threshold amount,a determination (e.g., at 970) can be made that poor fit criteria hasbeen met or that a poor fit threshold has been reached. In response tosuch a determination, an improper fit indication can be generated whichcan include a prompt to the user to tighten one or more couplers 150associated with the lower leg 105 of the user 101. Additionally, in someembodiments, where a determination of improper fit is made, power,actuation capacity, range of motion, or other capacity of theexoskeleton system 100 can be limited for the safety of the user 101until a subsequent fit test determines proper fit to a user 101.

The described embodiments are susceptible to various modifications andalternative forms, and specific examples thereof have been shown by wayof example in the drawings and are herein described in detail. It shouldbe understood, however, that the described embodiments are not to belimited to the particular forms or methods disclosed, but to thecontrary, the present disclosure is to cover all modifications,equivalents, and alternatives.

What is claimed is:
 1. A method of performing a moving fit test on awearable pneumatic exoskeleton system coupled to a user: coupling thewearable pneumatic exoskeleton system to legs of a user, the wearablepneumatic exoskeleton system comprising: a left and right pneumatic legactuator unit respectively associated with a left and right leg of theuser, the left and right pneumatic actuator units each including: arotatable joint configured to be aligned with a rotational axis of aknee of the user wearing the pneumatic exoskeleton system, an upper armcoupled to the rotatable joint and extending along a length of an upperleg portion above the knee of the user wearing the pneumatic exoskeletonsystem, a lower arm coupled to the rotatable joint and extending along alength of a lower leg portion below the knee of the user wearing thepneumatic exoskeleton system, and an inflatable bellows actuatordefining a bellows cavity, the inflatable bellows actuator configured toextend along a length of the bellows actuator when pneumaticallyinflated by introducing pneumatic fluid into the bellows cavity andconfigured to actuate the upper arm and lower arm; a pneumatic systemconfigured to introduce pneumatic fluid to the bellows actuators of thepneumatic leg actuator units to independently actuate the bellowsactuators, and an exoskeleton computing device including: a plurality ofsensors, a memory storing at least a moving fit test program, and aprocessor configured to execute the moving fit test program to controlthe pneumatic system; and executing the moving fit test program by theprocessor to cause pneumatic exoskeleton system to: generate a movingfit testing position indication instructing the user to perform orprepare to perform one or more movements for the moving fit test;determining that the user has assumed an initial moving fit test dynamicstance phase; actuating the left and right pneumatic leg actuator unitswhile the user is performing the one or more movements for the movingfit test; determining a first configuration of the upper arm and lowerarms of the left and right pneumatic leg actuator units generated inresponse to the actuating the left and right pneumatic leg actuator unitwhile the user is performing the one or more movements for the movingfit test, the determining of the first configuration based at least inpart on data obtained from one or more of the plurality of sensors;determining a change from the first configuration of the upper arm andlower arm of the left and right pneumatic leg actuator units while theuser is performing the one or more movements for the moving fit test,the determining based at least in part on data obtained from one or moreof the plurality of sensors; determining that the change from the firstconfiguration corresponds to an improper fit of at least one of the leftand right pneumatic leg actuator units coupled the legs of the user; andgenerating an improper fit indication that indicates improper fit of atleast one of the left and right pneumatic leg actuator units coupled thelegs of the user.
 2. The method of claim 1, wherein the one or moremovements includes at least one of: walking, running, standing from asitting position, sitting from a standing position, squatting, andbending or extending a single leg.
 3. The method of claim 1, wherein thedetermining the change from the first configuration of the upper arm andlower arm of the left and right pneumatic leg actuator units while theuser is performing the one or more movements for the moving fit testcomprises: determining a displacement angle of one or both of the upperarm and lower arm of the right pneumatic leg actuator.
 4. The method ofclaim 1, wherein the right pneumatic leg actuator upper arm and lowerarm are coupled to the right leg of the user via a respective pluralityof couplers of a set of couplers, with each of the couplers of the setof couplers including a strap that surrounds a portion of the right legof user; and wherein the improper fit indication includes an indicationof one or more of the couplers of the set of couplers being improperlysecured to the right leg of the user and an indication that the othercouplers of the set of couplers are properly secured to the right leg ofthe user.
 5. A method of performing a moving fit test on a leg actuatorunit coupled to a user, the method comprising: coupling the leg actuatorunit to a leg of a user, the leg actuator unit comprising: a jointconfigured to be aligned with a knee of the leg of the user wearing theleg actuator unit; an upper arm coupled to the joint and extending alonga length of an upper leg portion above the knee of the user wearing theleg actuator unit; a lower arm coupled to the joint and extending alonga length of a lower leg portion below the knee of the user wearing theleg actuator unit; and an actuator configured to actuate the upper armand lower arm; actuating the leg actuator unit while the user isperforming one or more movements for the moving fit test; determining afirst configuration of the upper arm and lower arms of the leg actuatorunit generated in response to the actuating the leg actuator unit whilethe user is performing one or more movements for the moving fit test;determining a change from the first configuration of the upper arm andlower arm of the leg actuator unit while the user is performing the oneor more movements for the moving fit test, the determining based atleast in part on data obtained from one or more sensors associated withthe leg actuator unit; determining that the change from the firstconfiguration corresponds to an improper fit of the leg actuator unitcoupled the leg of the user; and generating an improper fit indicationthat indicates improper fit of at least leg actuator units coupled theleg of the user.
 6. The method of claim 5, further comprising generatinga moving fit testing position indication instructing the user to performor prepare to perform one or more specified movements for the moving fittest.
 7. The method of claim 5, wherein determining the change from thefirst configuration comprises determining a displacement angle of one orboth of the upper arm and lower arm of the leg actuator unit.
 8. Themethod of claim 5, wherein the leg actuator upper arm and lower arm arecoupled to the leg of the user via a respective plurality of couplers ofa set of couplers; and wherein the improper fit indication thatindicates improper fit of the leg actuator unit to the leg of the userfurther includes an indication of one or more of the couplers of the setof couplers being improperly secured to the leg of the user.
 9. Themethod of claim 8, wherein with each of the couplers of the set ofcouplers including a strap that surrounds a portion of the leg of theuser.
 10. A method of performing a fit test on an actuator unit coupledto a user, the method comprising: determining a first configuration ofthe actuator unit generated in response to actuating the actuator unitwhile the user is performing one or more movements for the fit test;determining a change from the first configuration of the actuator unitwhile the user is performing the one or more movements for the fit test;determining that the change from the first configuration corresponds toan improper fit of the actuator unit coupled the user; and generating animproper fit indication that indicates improper fit of at least legactuator units coupled the user.
 11. The method of claim 10, furthercomprising generating an improper fit indication that indicates improperfit of the actuator unit to the user.
 12. The method of claim 11,wherein the improper fit indication that indicates improper fit of theactuator unit to the user includes an indication of a specific portionof the actuator unit being improperly fit to the user.
 13. The method ofclaim 12, wherein the actuator unit is coupled to the user via a set ofcouplers; and wherein the improper fit indication that indicatesimproper fit of the actuator unit to the user further includes anindication of one or more of couplers of the set of couplers beingimproperly secured to the of the user and at least an implicitindication that the other couplers of the set of couplers are properlysecured to the user.
 14. The method of claim 10, wherein the actuatorunit comprises: an actuator joint configured to be aligned with a bodyjoint of the user wearing the actuator unit; an upper arm coupled to theactuator joint and extending along a length of an upper body portionabove the body joint of the user wearing the actuator unit; a lower armcoupled to the actuator joint and extending along a length of a lowerbody portion below the body joint of the user wearing the actuator unit;and an actuator configured to actuate the upper arm and lower arm. 15.The method of claim 14, wherein determining the change from the firstconfiguration comprises determining a displacement angle of one or bothof the upper arm and lower arm of the leg actuator unit.
 16. The methodof claim 10, wherein the one or more movements includes at least one of:walking, running, standing from a sitting position, sitting from astanding position, squatting, and bending or extending a single leg. 17.The method of claim 10, further comprising limiting a capability of theactuator unit in response to determining that the change from the firstconfiguration corresponds to an improper fit of the actuator unit to theuser.
 18. The method of claim 17, wherein limiting a capability of theactuator unit in response to determining that the change from the firstconfiguration corresponds to an improper fit of the actuator unit to theuser comprises limiting power of the actuator unit.
 19. The method ofclaim 10, wherein the fit test is initiated by the user, a technician,or automatically based on a determination of exoskeleton performanceissues.